You think everything online is legal and always subject to copyright laws?
I'll bet that despite the measures in place, Revenge of the Sith will be available for download within 12 hours of the first theatrical release.
Again though, I am only playing Devil's Advocate.
In order for someone to put these works online, they have to have access to the works. RAH's works are mostly long, long out of print, and some of them were never collected anywhere, but they appeared in long vanished magazines like Campbell's "Amazing". LAPL has those in their rare documents section - the only extant copies of them, in some cases.
Putting Revenge Of The Sith online is trivial - it's current, it's already digital, and you could get a take off the monitor in any projection booth. If you want hard, find a paperback second edition copy of "Beyond This Horizon" and put it online complete with the wonderful Golden Age illustrations. I've been looking for that book for a decade now; and the only copies I've seen are in one of two libraries and are in sadly decayed shape. Not available in any store, at any price. I'll wait while you go find one that's in good enough shape to be scanned in. I'm very sure I'm going to be waiting a very long time.
As a practical matter, it's far easier to bootleg a movie than it is to scan in all the pages of a book.